Suction device and suction method for the disposal of dust in milling machines

ABSTRACT

Disclosed is an automotive milling machine for machining ground surfaces, comprising an engine frame ( 2 ), a movable milling drum ( 8 ) which is mounted on the engine frame ( 2 ), at least one conveying device ( 14, 18 ) which is arranged on the engine frame ( 2 ) and takes over the milled material ( 3 ) from the milling drum ( 8 ) at a transfer location ( 5 ), and a device ( 20 ) sucking off the air that is polluted with dust and fumes. The milled material ( 3 ) is enclosed by a duct ( 16, 16   a,    16   b ) on the at least one conveying device ( 14, 18 ), said duct ( 16 ) being separated into two sections ( 16   a,    16   b ). The suction device ( 20 ) is connected to the first section ( 16   a ) of the duct ( 16 ) downstream from the first transfer location ( 5 ) and sucks off the air that has been polluted during milling at the milling drum ( 8 ) as well as inside the first section ( 16   a ) of the duct ( 16 ) essentially in the direction in which the material is conveyed.

BACKGROUND OF THE INVENTION

The invention relates to an automotive milling machine for machiningground surfaces, particularly roadways, as well as to a method for thedisposal of dusts and fumes at a milling machine, which are producedduring the milling.

Such milling machines are also called road milling machines.

A front loader milling machine, for example, is known from DE-A-39 03482 or DE-A 38 31 161. The known milling machines comprise an automotiverunning gear with a pair of front wheels and a pair of rear wheels. Therunning gear supports a machine frame in which a milling drum issupported transverse to the traveling direction. To achieve atransportation of the milled-off material that is as complete aspossible, the milling drum is typically surrounded by a housing in whichthe wall pointing towards the traveling direction is configured as acovering shield with a passage opening for the milled-off material. Thatwall that is the rear one in traveling direction is configured as astripper and pressed against the milled surface to seal the drum box tothe rear in order to supply the milled-off material completely totransportation. The milling drum throws the material worked off by themilling drum onto a first band conveyor which transfers the worked-offmaterial onto a stacker belt at the front end of the milling machine,which is pivotable with respect to its inclination and laterally for thetransport onto a floor of a truck.

Another embodiment of these road milling machines, the so-called rearloader milling machine, is known from DE-A 34 05 473, for example. Here,the passage opening for the milled-off material is located in the wallof the drum housing pointing toward the direction opposite to thetraveling direction and also being configured as a stripper. Thematerial milled off by the milling roll is directly transferred onto theband conveyor serving as stacker belt and being arranged at the rear endof the milling machine to transport it onto a truck. Like the stackerbelt of the front loader milling machine, the stacker belt of the rearloader milling machine may also be pivotable in its inclination andlaterally.

The milling drum of such road milling machines is fitted with chiseltools forming a conveying helix transporting the milled-off material tothe passage opening of the covering shield.

By milling off the ground surface and by transporting the milled-offmaterial, dusts and fumes are produced which may impair theoperativeness of the conveying devices, on the one hand, and worsen theworking conditions for the machine operator on the driver stand and forthe remaining operating personnel about the milling machine, on theother hand, and possibly even be an obstacle to the view for the trafficthat is possibly passing.

From EP 0 971 075, it is already known to provide the band conveyors ofa milling machine with a hood, to suck off the produced dust at themilling drum and under the hood of the band conveyors opposite to thetransport direction and to dispose of it via a blower and a filteringmeans at the rear end of the milling machine. It is disadvantageous thatthe sucking is effected at the band conveyors opposite to the transportdirection. Due to the fact that the dusty air is sucked off rearward andopposite to the actual transport direction of the material, considerableadditional efforts for the conversion of the machine and a distinctlyhigher air output of the blower are required. The use of a radial fan atthe rear end of the milling machine has the disadvantage that it is notpossible to achieve a sufficiently high airflow at the band conveyorsthat are at the front in the direction of travel. Finally, the particlesdiscarded at the blower and the cyclone filter are thrown onto theground surface again whereby the ground surface just milled off issoiled again. The cyclone filter provided at the rear end of the machineis only able to segregate the coarser particles but not the respirablefine dusts so that the arrangement of the air outlet at the rear end ofthe milling machine is arranged too close to the driver stand. The sameapplies to a mesh-shaped filter that is not able to segregate respirabledusts either. Another disadvantage of prior art consists in that dustsand fumes are blown off at the rear end of the milling machine near thedriver stand and that, moreover, dusts are inevitably produced anew whenthe milled-off material is thrown off at the front band conveyor.

SUMMARY OF THE INVENTION

Therefore, it is the object of the invention to provide a millingmachine of the afore-mentioned kind as well as a method for the disposalof dusts and fumes where dusts and fumes produced upon milling andconveying can be sucked off with lower requirements as to the machinesand with higher efficiency and disposed of together with the worked-offmaterial.

The invention advantageously provides that the suction device isconnected to a first section of the duct allocated to the conveyingdevice downstream from the first transfer location and sucks off the airthat has been polluted during milling essentially in the direction inwhich the material is conveyed in the first duct section, the pollutedair being sucked off at the milling drum as well.

The invention permits a simple construction where the structure of amilling machine does not have to be changed fundamentally so that aretrofitting of existing milling machines is possible as well.

Sucking off the polluted air in the first duct section permits a suckingnear the greatest source of pollution where dusts and fumes areproduced. At the milling drum, dusts are produced by breaking up theground surface and fumes are produced because of the high temperaturesduring milling, e.g., during milling off asphalt materials. As thingsdevelop, dusts may also be produced in the region of the conveyingdevice by the transport of the milled-off material. The arrangement ofthe suction device in the first duct section of the conveying devicepermits the application of a strong airflow in the region of the millingroll and the first duct section whereby the discharge of dusts or fumesat the milling roll or at the first duct section is avoided. Therefore,dusts and fumes can be sucked off reliably in the working range of themilling roll and at the location of transfer from the milling roll ontothe conveying device. An essential advantage is the improvement of theworking conditions on the driver stand and in the environment of themilling machine and the low fault liability of the conveying device.Moreover, the milled ground surface is left clean. An essentialadvantage of the disposal of the dusts and fumes via the discharge ofthe conveying means consists in that the development of dust is nearlyunavoidable at this site since the milled-off material is thrown offonto the floor of a transport vehicle from a height of several meters.The invention advantageously provides that the dusts and fumes aredisposed of exactly where the development of dust is unavoidable anyway.For reasons of working security, standing there is strictly forbiddenanyway. The working area on the driver stand and next to the machine,however, is freed from dusts and fumes and particularly from theirrespirable fractions.

Preferably, the second duct section is separated from the first ductsection by separating means for blocking up an airflow without hinderinga conveyance of the material.

Preferably, it is provided that the suction device comprises a suctionduct connected to the first duct section and an axial fan integratedinto the suction duct. The polluted air is disposed of by the first ductsection via the suction duct, the axial fan integrated in the suctionduct providing for a high negative pressure and a high airflow speed atthe suction locations. Another advantage of the axial fan consists inthat it can be integrated into the suction duct and is thus arranged ina room-saving manner and simultaneously, it can be arranged close to thesuction locations. Another advantage of the axial fan is itsindifference to dirt and its self-cleaning effect. The high suckingpower does not only permit to suck off respirable dusts and fumes but,moreover, of coarser dust particles as well.

The suction device disposes of the polluted air at that site where dustdevelops anyway as a consequence of the discharge of the milled-offmaterial from the conveying device.

According to an embodiment of the invention, it is provided that thedownstream end of the suction duct opens into an upper section of thesecond duct section formed by the conveying device. By returning thesucked-off polluted air into the second duct section of the conveyingdevice, it is possible to dispose of the polluted air together with themilled-off material far from the driver stand of the milling machine. Bythe polluted air entering into the second duct section, the second ductsection is also sucked off in the direction in which the material isconveyed because of the injection effect.

The downstream end of the suction duct opens into a second duct sectionseparated from the first duct section by separating means for blockingup an airflow without hindering the transport of the milled-offmaterial. Consequently, a divided duct is formed which extends over theentire length of the conveying device, the separations being effected bythe separating means which, on the one hand, do not hinder the transportof the milled-off material and, on the other hand, prevent an airflowopposite to the direction in which the material is conveyed. Thus, theduct sections are sealed off with respect to each other in asubstantially air-tight manner.

Preferably, it is provided that the conveying device comprises at leastone band conveyor with a conveyor belt and that sealing means for theduct consist of hoods sealing against the conveyor belt or against thehousing of the band conveyor. Thus, the hoods form a closed ducttogether with the conveyor belt or together with the housing of the bandconveyor so that the milled-off material travels through the conveyingdevice in a completely peripherally enclosed manner. Thus, no dusts orfumes may emerge to the outside.

A second conveying device may take over the milled-off material at theend of the first conveying device at a second transfer location.

The transfer location between the first and the second conveying deviceis sealed with flexible sealing means mounted to at least one of theconveying devices. Smaller gaps do not matter since both the first ductsection and the lower portion of the second duct section are under anegative pressure so that no polluted air can escape at possibleleakages but air is sucked at most.

Preferably, the suction duct enters into the second duct section at anacute angle and shortly in front of the discharge end. The entranceangle reinforces the injection effect so that the lower portion of thesecond duct section is reliably sucked as well, without any additionalsuction device.

In a preferred embodiment of the invention, it is provided that anagglomeration means is arranged behind the junction of the suction ductand the second duct section. By means of the agglomeration means, thedusts and fumes can be agglomerated and condensed, respectively, so thatthey can be disposed of together with the milled-off material.

The agglomeration means may consist of, e.g., a water spraying meansarranged at the outlet of the conveying means. By means of the waterspraying means, the dusts can be bound and agglomerated and the fumescan be condensed as well.

Alternatively, with respect to the dusts, it is also possible toprecipitate them electrostatically.

Between the first and the second duct section of the conveying device,at least one flexible flap is arranged as a separating means downstreamand not far from the air intake fitting of the suction device, blockingup the first duct section of the conveying device against air enteringopposite to the direction in which the material is conveyed. Themilled-off material can pivot the flap in the direction in which thematerial is conveyed whereas the entry of air opposite to the directionin which the material is conveyed is prevented. The negative pressure infront of the flap reinforces the sealing by sucking the flap onto themilled-off material on the conveyor belt.

If the conveying device is formed of several conveying devices, theseparating means is preferably provided at the first conveying device.

The flap may be repeatedly divided by vertically extending slots so thatthe flap are able to adapt to the contour of the material conveyed onthe band conveyor. Preferably, several flaps, divided and/or undivided,are provided behind each other between the first and the second ductsection.

At the sides of the at least one conveyor belt, the conveying devicecomprises hood supports sealed with respect to the conveyor belt by anelastic lip. Thus, the conveyor belt, together with the elastic lip, thehood support and the hoods, forms a completely closed duct cross sectiontightly enclosing the conveyed milled-off material. Alternatively, theduct cross section may also be formed by several hood portions.

According to the method for the disposal of the air polluted with dustsand fumes during milling at a milling machine for machining groundsurfaces, where the material milled off by a milling drum is disposed ofvia at least one conveying device.

According to a preferred embodiment, the following steps are provided:

-   -   forming a duct about the milled-off material on the conveying        device, divided in the transport direction, comprising a first        duct section and a second duct section connected to the first        duct section, the milled-off material being able to enter into        the second duct section from the first duct section in an        unhindered manner, an airflow between the first and the second        duct section and particularly opposite to the material flow        direction, however, being prevented,    -   sucking off the polluted air in the first duct section of the        conveying device by means of a blower in the direction in which        the milled-off material is conveyed, and    -   guiding the polluted air in a suction duct substantially        parallel to the direction in which the milled-off material is        conveyed,    -   introducing the polluted air into the second duct section of the        conveying device before the milled-off material is thrown off.

Hereinafter, embodiments of the invention are explained in detail withreference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a first embodiment of a front loader milling machineaccording to the invention.

FIG. 2 shows the suction device connected to the conveying device.

FIG. 3 shows a cross section through the conveying device in the regionof the first duct section.

FIG. 4 shows a view of the front-side end of the first band conveyorwith the connected suction duct.

FIG. 5 shows a second embodiment of a rear loader milling machineaccording to the invention.

FIG. 6 shows a cross section through the conveying device according to asecond embodiment of a hood.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A milling machine 1 for machining surfaces in the configuration of afront loader milling machine is shown in FIG. 1. It goes without sayingthat the invention is also applicable to different milling machineswhich are provided with at least one conveying device 14,18.

The milling machine 1 serves to mill off ground surfaces, particularlyroadways of asphalt, concrete or the like. The milling machine 1comprises a running gear with, e.g., four drive units 4 formed by chainrunning wheels, which supports the engine frame 2. In the engine frame2, a milling drum 8 is supported which extends transversely to thetraveling direction. The adjustment of the milling depth is effected bymeans of the height adjustment of the drive units 4. The milling machine1 illustrated in FIG. 1 is also referred to as a front loader millingmachine since it conveys the milled-off material in traveling directionto the front onto a transport vehicle 10. In the traveling direction infront of the milling drum 8, a first conveying device 14 consisting of aband conveyor and comprising a conveyor belt 15 is arranged in a shaft 9of the engine frame 2 extending at an inclination angle in the engineframe 2. The first conveying device 14 conveys the milled-off material 3on the conveyor belt 15 to a second conveying device 18 consisting of aband conveyor and comprising another conveyor belt 19. The secondconveying device 18 is height-adjustable via an adjustable inclinationangle and additionally, it is adapted to be pivoted laterally and, forexample, by ±30 so that transport vehicles 10 standing adjacent the laneof the front loader milling machine can be loaded as well. As analternative to band conveyors, the use of a conveyor worm, for example,which is arranged in a duct is possible as well.

To achieve a transport of the milled-off material as complete aspossible, the milling drum 8 is typically surrounded by a drum box 58where the wall pointing towards the traveling direction is configured asa shield 52 with a passage opening 56 for the milled-off material.

The milling drum 8 is provided with helically arranged chisel toolsarranged such that the milled-off material is transported to the passageopening 56 in the shield 52. At the end of the drum box 58 that islocated to the rear in traveling direction, a wall 60 of the drum box 58forming a tight closure with the milled ground surface is provided,which strips off the milled ground surface so that no fragments of themilled-off material remain on the milled ground surface. With its loweredge, the wall 60 is pressed hydraulically against the ground surface toachieve a sealing as good as possible.

At the engine frame 2, a band shoe 50 as a band protecting andsupporting means is height-adjustably mounted in a guide. The band shoe50 receives the rear end of the first conveying device 14. The passageopening 56 of the drum box 58 forms a first transfer location 5 wherethe milled-off material is transferred from the milling drum 8 onto thefirst conveying device 14.

In the embodiment of FIG. 1, the driver stand is located above themilling drum 8 but may also be arranged in the rear or front region ofthe engine frame 2 as is typical with milling machines.

FIG. 2 shows the first conveying device 14 in detail.

The conveying device 14 is mounted in a shaft 9 of the engine frame 2,which is preferably arranged centrally, and is adapted to be easilydismounted from the band shoe 50 for maintenance purposes and to beremoved through the shaft 9.

The conveying device 14 with the conveyor belt 15 comprises a hood 22forming, together with the upper carrying run 15 a of the conveyor belt15, a duct section 16 a of a duct 16 extending from the drum box 56 tothe end of the second conveying device 18. As can be seen in detail inthe cross section of FIG. 3, the hood 22 of the first conveying device14 is fastened to the frame of the first conveying device 14 by means ofhood supports 44. At both sides of the band conveyor, elastic lips 46are mounted to the hood supports 44 and touch the carrying run 15 a ofthe conveyor belt 15 in the border portion over the entire length of thecarrying run 15 a.

Likewise, the second conveying device 18 is provided with a hood 26 alsosealed with respect to the carrying run of the band conveyor 19 viasealing lips 46 and mounted at corresponding hood supports 44. Thus, theduct 16 is sealed in a dust- and gas-tight manner with respect to thesurroundings.

In the upper region of the hood 22 near the discharge end but at adistance thereto, the hood 22 of the first conveying device 14 comprisesa connection piece 23 projecting substantially vertically upward, towhich a suction duct 24 is connectible. To this end, the engine frame 2comprises a substantially vertical shaft 25 in its center through whichshaft the suction channel 24 can come out upward from the engine frame2. In a first section of the suction duct 24, an axial fan 28 isintegrated in the suction duct 24. This has the advantage that the roomrequired for a blower is minimized. The axial fan 28 permits a high airoutput and therefore, it generates a correspondingly high negativepressure in the first duct section 16 a and the drum box 56 surroundingthe milling drum 8. Therefore, the dusts and fumes produced during themilling process are sucked off reliably and with high efficiency via thesuction duct 24. In the region of the first transfer location 5, i.e.,at the lower end of the hood 22 and at the passage opening 56 of thedrum box 58 and the band shoe 50, respectively, flexible rubber mats maycircumferentially seal the transfer location 5. Smaller leakages of thedrum box 56 or between the duct 16 and the drum box 56 are unimportantsince, due to the negative pressure, polluted air cannot escape but atmost, air is sucked in from the environment. As can be seen best fromFIG. 4, the upper end of the hood 22 is provided with flexible flaps 36as separating means between the first and the second duct section 16 a,16 b, which, on the one hand, let the milled-off material 3 on theconveyor belt 15 pass and, on the other hand, prevent an airflowopposite to the transport direction of the first conveying device 14. Ifonly a single band conveyor is provided, the separating means arelocated in the middle of the single conveying device.

To seal the first duct section 16 a as well as possible at its upperend, the flaps 36 are provided with slots. Preferably, several flaps 36are arranged behind each other to achieve an improved air sealingbetween the duct sections 16 a, 16 b.

As can be seen best in FIG. 3, the conveyor belt 15 is guided oversupporting rollers 62,64, the carrying run 15 a forming a substantiallyU-shaped channel because of a corresponding inclination of thesupporting rollers 64. The lower supporting roller 62 supports the lowerrun 15 b of the conveyor belt 15. As can be seen from FIGS. 3 and 4,webs 17 are located on the surface of the conveyor belt 15, whichimprove the transport of the milled-off material 3 on the conveyor belt15.

At the upper end of the conveying device 14, the milled-off material 3is transferred into a receiving funnel 35 of the second conveying device18 at the second transfer location 7, whereby the milled-off material 3is transported over the conveyor belt 19 to the discharge end anddisposed of onto the transport vehicle 10.

The transition location at the transfer location 7 is enclosed bysealing means consisting of flexible mats 30 so that the first conveyingdevice 14 and the second conveying device 18 form a circumferentiallysealed duct 16 that is continuous in the direction in which the materialis conveyed.

At its other end, the suction duct 24 is connected to the hood 26 of thesecond conveying device 18, the connection piece 27 preferably enteringinto the duct section 16 b at a low angle to produce an injection effectin the duct section 16 b at the high flow speed of the sucked-offpolluted air, whereby the lower portion of the duct section 16 b issucked as well. To permit an airflow, gaps for sucking air can be leftfree at suitable sites in the region of the second transfer location 7,e.g., at the sealing means 30. At the upper end of the second conveyingdevice 18, the milled-off material is thrown off, the sucked-off airloaded with dust and fumes with the milled-off material 6 being disposedof together with the milled-off material 3. At the discharge end of thesecond conveying device, an agglomeration means 34 is preferablyprovided by means of which dusts can be bound and possibly existingfumes can be condensed. The agglomeration means 34 may consist of awater spraying means, the dusts and fumes being segregated, for example,with a spray. Preferably, the agglomeration means 34 is arranged outsidethe duct section 16 b at the discharge end of the second conveyingdevice 18, but it could also be arranged within the second duct section16 b.

The milling machine 1, however, could also be used without anagglomeration means 34 since the dusts and fumes are disposed of veryfar from the driver stand so that the working conditions on the driverstand and in the working area about the machine are considerablyimproved even without an agglomeration means 34.

FIG. 5 shows a second embodiment of the invention with reference to theexample of a rear loader milling machine 11 with only a single conveyingdevice 14. In a rear loader milling machine, the passage opening for themilled-off material 3 is located in the wall 61 of the drum box 58,which points towards the direction opposite to the traveling directionand is configured as a stripper. Directly at this transfer location 5,the material 3 milled off by the milling drum 8 is transferred onto theband conveyor of the single conveying device 14, which is arranged atthe rear end of the rear loader milling machine 11. The conveyor belt 15of the conveying device 14 conveys the milled-off material onto atransport vehicle 10. Like the conveying device 18 of the embodiment ofFIG. 1, the conveying device 14 is pivotable in its inclination as wellas laterally.

As can be seen from FIG. 5, the connection piece 23 is directlyconnected to an upper hood portion 22 a of the conveying device 14 atthe lower end. As in the first embodiment, flexible flaps 36 abutting onthe carrying run 15 a of the conveyor belt 15, as is fundamentallyapparent from FIG. 4, serve as separating means between the ductsections 16 a, 16 b. Preferably, several flaps are arranged behind eachother, which permit an unhindered transport of the milled-off material 3from the first duct section 16 a into the second duct section 16 b butlargely prevent an airflow between the two duct sections 16 a, 16 b. Thepolluted air sucked off via the suction duct 24 reenters into the duct16 at the upper end of the conveying device 14, namely into the ductsection 16 b near the discharge end of the conveying device 14.

FIG. 6 shows a second embodiment of a hood 22 formed of two hoodportions 22 a, 22 b.

Compared with the embodiment of FIG. 3, the sealing lips 46 may beomitted; in this case, the duct cross section is defined by matchinghood portions 22 a and 22 b.

Although a preferred embodiment of the invention has been specificallyillustrated and described herein, it is to be understood that minorvariations may be made in the apparatus without departing from thespirit and scope of the invention, as defined by the appended claims.

1. An automotive milling machine (1,11) for machining ground surfacescomprising an engine frame (2), a milling drum (8) supported on theengine frame (2), at least one conveying device (14,18) which isarranged on the engine frame (2) and takes over the milled-off material(3) from the milling drum (8) at a first transfer location (5), asuction device (20) for air that is polluted with dust and fumes, the atleast one conveying device (14,18) for the milled-off material (3) beingenclosed by a duct (16), the duct (16) enclosing the conveying device(14,18) being divided into first and second duct sections (16 a,16 b)with a second transfer location (7) being located therebetween, thesuction device (20) being connected to the first duct section (16 a) ofthe duct (16) downstream from the first transfer location (5) for themilled-off material (3), the suction device (20) sucks off air pollutedduring milling inside the first duct section (16 a) substantially in thedirection in which the milled-off material (3) is conveyed, and thesecond duct section (16 b) being separated from the first duct section(16 a) by means (36) for blocking airflow without hindering thetransport of the milled-off material (3).
 2. The milling machineaccording to claim 1, characterized in that the suction device (20)comprises a suction duct (24) connected to the first duct section (16a).
 3. The milling machine according to claim 2, characterized in thatthe suction duct (24) comprises an axial fan (28) integrated into thesuction duct (24).
 4. The milling machine according to claim 2,characterized in that a downstream end of the suction duct (24) opensinto the second duct section (16 b).
 5. The milling machine according toclaim 1, characterized in that the suction device (20) disposes of thepolluted air where dust develops as a consequence of the discharge fromthe conveying device (14,18).
 6. The milling machine according to claim1, characterized by means for sealing the duct (16) against the at leastone conveying device (14,18).
 7. The milling machine according to claim1, characterized in that the at least one conveying device (14,18)includes a band conveyor with a conveyor belt (15,19), and the duct (16)is formed of hoods (22,22 a,22 b,26) sealing against the conveyor belt(15,19) or against the housing of the at least one conveying device(14,18).
 8. The milling machine according to claim 1, characterized inthat a second conveying device (18) takes over the lied-off material atthe end of the first conveying device (14) at the second transferlocation (7), and that the second transfer location (7) between thefirst and the second conveying device (14,18) is circumferentiallysealed by flexible sealing means (30) connected to the conveying devices(14,18) so that a continuous duct is formed over both conveying devices(14,18).
 9. The milling machine according to claim 3, characterized inthat the suction duct (24) opens into the second duct section (16 b) ofthe conveying device (14,18) at an acute angle.
 10. The milling machineaccording to claim 1, characterized by means (34) for agglomerating thedusts and/or for condensing the fumes arranged behind a junction of thesuction duct (24) and the second duct section (16 b) of the at least oneconveying device (14,18).
 11. The milling machine according to claim 10,characterized in that the agglomerating means (34) includes means forspraying water arranged at the discharge end of the at least oneconveying device (14,18).
 12. The milling machine according to claim 1,characterized in that the separating means (36) between the first ductsection (16 a) and the second duct section (16 b) of the at least oneconveying device (14,18) include at least one flexible flap extendingover the entire open cross section of the duct section (16 a).
 13. Themilling machine according to claim 7, characterized in that hoodsupports (44) for the hoods (22,26) are mounted to the sides of a bandconveyor, and said hood supports being sealed against the conveyor belt(15,19) of the band conveyor by an elastic lip (46).
 14. A method ofdisposing of dusts and fumes produced during the milling of a groundsurface comprising the steps of milling a ground surface and therebyproducing milled-off material and an accompanying dust and fumes airadmixture, conveying the milled-off material and admixture along a firstsubstantially closed path of travel in a first direction toward atransfer location, transferring at the transfer location the milled-offmaterial from the first substantially closed path of travel to a secondsubstantially closed path of travel, conveying the milled-off materialalong the second substantially closed path of travel toward a dischargelocation, and blocking airflow beyond the first substantially closedpath of travel without blocking the transfer of the milled-off materialat the transfer location to the second substantially closed path oftravel whereby the admixture is substantially precluded from enteringatmosphere at the discharge location.
 15. The method as defined in claim14 including the step of agglomerating the sucked-off admixture with themilled-off material along the substantially closed second path of travelto thereby assure the admixture does not enter the atmosphere.
 16. Themethod as defined in claim 14 including the step of agglomerating thesucked-off admixture with the milled-off material contiguous thedischarge location to thereby assure the admixture does not enter theatmosphere.
 17. The method as defined in claim 14 wherein the suckingoff the admixture creates an airflow in the substantially closed firstpath of travel corresponding to the first direction.
 18. The method asdefined in claim 15 including the step of agglomerating the sucked-offadmixture with the milled-off material contiguous the discharge locationto thereby assure the admixture does not enter the atmosphere.
 19. Themethod as defined in claim 15 wherein the sucking off the admixturecreates an airflow in the substantially closed first path of travelcorresponding to the first direction.